I recently had a conversation with a friend about similar marks on
Chapin plow planes. Between the two of us, every example we've found
has matching marks on the inside of the mortise and the wedge. all of
the planes have different numbers and are unrelated to the model
number of the plow stamped on the toe of the plane. We both agree
these were used during protection/assembly to keep the parts together.
I've seen similar marks on many molding planes, but nothing as
consistent as those on the Chapin planes.

Josh in CT

On Wed, Jan 13, 2021 at 6:22 PM Kirk Eppler via OldTools
 wrote: